The District, the California Air Resources Board (ARB), and other air agencies throughout California operate an extensive air quality monitoring network. All of the air quality and meteorological data collected from this network are available in a user-freindly, centralized location on ARB's webpage through the button above.

ARB's AQMIS2 data webpage includes several tools:

The "Latest Ozone" and "Latest Year's Ozone" buttons provide summaries of ozone data for selected areas of the state, including the San Joaquin Valley. The detailed data available here can show how the Valley's recent ozone data compares to previous years or other areas of the state.

The "Air Quality Data" page allows a user to view data for any air quality parameter collected at any air monitoring site in California. Parameters include ozone, particulate matter (PM), and more.

The "Meteorological Data" page allows a user to view data for any meteorology parameter collected at any air monitoring site in California. Parameters include temperature, pressure, wind, and more.

The "Google Maps" button provides a user-controlled map that displays air quality data. Make selections on the right and click on 'update display'.

For example, ARB's "Air Quality Data" tool can generate a report of daily maximum ozone levels for a Valley county through the "Daily Data" tab:

Step 1: Select "Ozone", "ppb", and "Daily Max"

Step 2: Select an End Date. For example, you can select the current data to have the mose recent air quality data included in your search.

Step 3: Use the county field to select your county of interest.

Step 4: For your report type, you can use either "Week at a glance" or "Year at a glance"

Step 5: "Basin/County/Site" is often the most useful data sort order.

Click on "Retrieve Data" to display the data report. You can click on a value of interest to see the data by air monitoring site. Then, clicking on a value for a particular site on a particular day will show you the hourly data. Information on the air monitoring site is available by clicking on the site name.